Titlebook: ;

咆哮

Sturgeons, Gar-pikes & Bowfin,is is an immensely successful group and such is its diversity that classification poses problems. The scheme adopted here represents, with very minor modifications, some of the more recent attempts to clarify actinopterygian relationships, although it is certainly not the final statement, and much t

CLASP

ARC

Eels & Herrings,tarpons are powerful swimmers, much prized as sport fish, particularly in the Atlantic. These silvery fish with large scales contrast sharply with the eels in which the body is much elongated and naked or covered with very small scales.

chronology

Cods & Anglers,ave fishes, anglerfish and cod. Except for the Kentucky cave fishes and trout perches, which are confined to the fresh waters of North America, they are mainly stout-bodied, marine fishes. Most are carnivores and many species are viviparous. Some occur in shallow waters, for example the toadfish and

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aristocracy

Prologue: The Promise of Revival,through the true fishes, amphibians and reptiles to the birds and mammals. Each class of vertebrate tends to demonstrate particular biological concepts better than others. The fishes have sustained their dominance in aquatic environments for some 500 million years from the Ordovician Period to the p

OUTRE

https://doi.org/10.1007/978-1-349-15972-7the Cephalochordats, which have been treated in the Guide to Invertebrate Animals. Chordates are eucoelomate animals, that is their main body cavity, containing most of the large organ systems, is a true coelom. In this respect they resemble a number of invertebrate groups, such as the annelids and

輕彈

財(cái)產(chǎn)

Fabric

Socialism with Chinese Characteristics important step forward achieved in the evolution of jaws and hence the division of the vertebrates into Agnatha and Gnathostomata. The alternative would be fish-like forms (Pisces) and four-footed vertebrates (Tetrapoda).